Abstract
Life extensions of nuclear power plants to 60 and potentially 80 years of operation have renewed interest in long-term material degradation. One material being considered is concrete, with a particular focus on radiation-induced effects. Based on the projected neutron fluence values (E > 0.1 MeV) in the concrete biological shields of the US pressurized water reactor fleet and the available data on radiation effects on concrete, some decrease in mechanical properties of concrete cannot be ruled out during extended operation beyond 60 years. An expansion of the irradiated concrete database and a reliable determination of relevant neutron fluence energy cutoff value are necessary to ensure reliable risk assessment for extended operation of nuclear power plants.
Highlights
Over the last 15 years, more than 70 nuclear power plants (NPPs) in the USA have received approval to extend their licenses to operate up to 60 years
Every operating NPP is required to implement a reactor pressure vessel (RPV) surveillance program, and a wealth of information from these programs is publicly available from ADAMS [5]
To capitalize on this information, we implemented a two-pronged approach: (a) a search of ADAMS database was performed to collect data from the RPV surveillance programs, and (b) coupled neutron and gamma-ray transport calculations were performed for two selected pressurized water reactors (PWRs) to provide guidelines on how to extrapolate the pressure vessel flux/fluence data to the flux/fluence in the concrete of the biological shield
Summary
Over the last 15 years, more than 70 nuclear power plants (NPPs) in the USA have received approval to extend their licenses to operate up to 60 years. The license extension process has renewed the focus on longterm degradation processes in NPP materials. One material currently under consideration is concrete in the biological shields and other structures in NPPs. It is well known that concrete properties change over time due to slow hydration, crystallization of amorphous components, reactions between cement paste and aggregates, and the effects of the local environment such as humidity, temperature, and for NPP concrete, radiation exposure. In this paper we will concentrate on the effects of radiation.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
